1. Field of the Invention
The present invention relates to vehicle air-conditioning units mainly for use in automobiles.
2. Description of the Related Art
FIG. 10 is a side view of an exemplary conventional vehicle air-conditioning unit (Japanese Patent Application No. H09-020128) An air-conditioning unit 100a shown in the figure has a unit case 100b in which an air passage is formed. The unit case 100b is provided with a face outlet 100c, a defroster outlet 100d and a foot outlet 100e through which air flows out of the unit.
In order to control the amount of air flowing out through the face outlet 100c, the defroster outlet 100d and the foot outlet 100e, a first mode door 100f and a second mode door 100g are disposed in the air passage. In this air-conditioning unit, the proportions of air flowing out through the outlets are adjusted for each mode (e.g., a face mode, a foot mode, a bi-level mode and a defroster mode). For this, rotations of the mode doors 100f and 100g are interlinked by a link mechanism 110. The link mechanism 110 includes a first lever 111 fixed to a rotary shaft of the first mode door 100f, a second lever 112 fixed to a rotary shaft of the second mode door 100g, a main link 114, and an intermediate link 113. The main link 114 is driven (rotated in this example) by a driving force from a driving means to rotate the levers 111 and 112. The intermediate link 113 is interposed between the main link 114 and a given lever (the second lever 112 in this example) to rotate the given lever in a direction opposite to that of another lever (the first lever 111 in this example).
More specifically, the main link 114 is rotatably mounted to the unit case 100b, and has three arms which extending in three different directions from the pivot. A first arm is provided with an engaging pin 114n movably fitted in a cam groove 111m of the first lever 111. A second arm is provided with an engaging pin 114p movably fitted in a cam groove 113k of the intermediate link 113. A third arm is provided with a mounting hole 114q to which a driving cable is attached. The intermediate link 113 is rotatably mounted to the unit case 11b, and has two arms which extending in two different directions from the pivot. A first arm is provided with an engaging pin 113j movably fitted in a cam groove 112i of the second lever 112. A second arm is provided with the cam groove 113k in a given shape.
Since the components of the link mechanism 110 (the levers 111 and 112, the intermediate link 113 and the main link 114) are exposed outside of the unit case 100b, the components may be accidentally damaged during vehicle assembly.
In the structure of the air-conditioning unit 100a, the components are mounted to the unit case 100b one by one in predetermined order, resulting in a complicated mounting operation of the link mechanism 110 and increased production costs.